Report Urges Airlines to Address Temperature, Humidity Hazards

A report published last month by the National Academies of Sciences, Engineering, and Medicine on temperature conditions in passenger aircraft cabins recommends that airlines address temperature and humidity hazards through their safety management systems. The committee convened to study how aircraft cabin temperatures affect the health and safety of flight attendants and passengers found that serious health effects related to extreme temperatures in aircraft cabins are uncommon but emphasized that thermal discomfort, which can occur at less extreme temperatures, has the potential to affect cognition and behavior. For example, thermal discomfort may impair flight attendants’ concentration and decision-making abilities, and can affect passengers’ mood and emotional responses, which could contribute to unruly behavior. Both groups are limited when it comes to leaving or modifying the environment of aircraft cabins, which makes managing temperature-related risks “essential for safe air travel,” the report states.

According to the report, aircraft cabin temperatures are most difficult to control during ground operations, when conditions “are more likely to approach thresholds at which heat-related stress would be expected, in part because of higher humidity levels.” Ground-based air-conditioning units are intended to help maintain acceptable cabin temperatures while aircraft are on the ground, but the committee found that this equipment sometimes malfunctions, is not available or not used, is improperly connected, or has insufficient capacity. Extreme outdoor temperatures can further complicate efforts to control cabin temperatures.

The report explains that while the Federal Aviation Administration (FAA) does not specify which hazards airlines must address through safety management systems, the agency can provide guidance to help air carriers manage temperature and humidity hazards within these systems. Such guidance should focus on “the acceptable duration of thermal exposure where cabin temperatures and humidity levels may approach health and safety limits,” the report recommends. Further actions FAA can take to help improve thermal control on aircraft are to update an advisory regarding ground operations without cabin ventilation and issue a safety alert for operators that focuses on how cabin temperatures and humidity can affect flight crew and passengers.

The report was congressionally mandated and sponsored by the U.S. Department of Transportation. It can be accessed via the National Academies website.